Device for winding-off yarn ends

ABSTRACT

Devices for detaching and winding off the exposed yarn end from a body of wound-up yarn on a bobbin by means of compressed air are disclosed, paricularly for use with automatic thread connection devices of ring spinning machines. Each device comprises a holder for a bobbin and a driving device for moving the bobbin to-and-fro in the axial direction relatively to at least three jet nozzles distributed equidistantly round the bobbin. The nozzles are set at an angle of about 45* to the bobbin axis so as to supply jets of compressed air that detach and wind off the yarn end which is received by a reception tube. The bobbin may remain displaced from the reception tube or alternatively the bobbin may be inserted in the tube, in which case the nozzle jets are directed into an annular gap between the bobbin and tube.

United States Patent [1 1 Vignon 5] Mar. 4, 1975 DEVICE FOR WINDING-OFF YARN ENDS Primary Examiner-Donald E. Watkins [75] Inventor: Louis Vignon, Geneva, Switzerland ABSTRACT {73] Assignee: Heberlein Hispano SA,

vemiepGeneva, Switzerland Devices for detaching and winding off the exposed yarn end from a body of wound-up yarn on a bobbin Flledi 1974 by means of compressed air are disclosed, paricularly [211 App]. NO 439 124 for use with automatic thread connection devices of ring spinning machines. Each device comprises a holder for a bobbin and a driving device for moving i 1 Foreign Appllcatlon y Data the bobbin to-and-fro in the axial direction relatively Feb. 2. 1973 Switzerland 1547/73 to at least three jet nozzles distributed equidistantly round the bobbin. The nozzles are set at an angle of [52] US. Cl. 57/34 R, 57/34.5 about 45 to the bobbin axis so as to supply jets of [5 l] Int. Cl. DOlh 13/00, DOlh 15/00 compressed air that detach and wind off the yarn end [58] Field of Search 57/34 R, 34 TT, 34.5, 56, which is received by a reception tube. The bobbin 57/54, 106, 107 may remain displaced from the reception tube or alternatively the bobbin may be inserted in the tube, in [56] REFERENCES CITED which case the nozzle jets are directed into an annular UNITED STATES PATENTS gap between the bobbin and tube. 3,511,041 5/1970 Korikovsky et al 57/34.R 3,374,616 3/1968 Hidden et al 57/34.R XR 3,546,870 12/1 70 Schewe et al 57/34.R XR 7 Claims, 4 Drawing Figures 3,807,I55 4/1974 Miyazaki et al 57/34.5 R

z i\ l 6 l DEVICE FOR WINDING-OFF YARN ENDS Field of the Invention The present invention relates to a device for detaching and winding off the yarn end from a wound-up yarn body on a bobbin by means of air under pressure, especially for automatic thread connection devices of ring spinning machines.

Description of the Prior Art Devices of this type for searching and winding off yarn ends are known and frequently used in various embodiments especially with automatic yarn connection devices. Most such devices are then conveived so that at first the wound-up yarn body is brought to rotation, then brought into engagement with a brush which lifts the yarn end from the surface of the wound-up yarn body and then removes the detached end by means of compressed air.

It is also known to replace the brush by ajet of compressed air which effects detaching of the yarn end from a rotating body of wound-up yarn, the final detaching being effected by centrifugal force, and the winding off by an additional source of suction air.

The known devices as a whole are complicated and subject ot frequent disturbances due to their construction. A particular disadvantage consists in that a special driving device must be provided which rotates the bobbin during winding off. Furthermore, besides the device for detaching the yarn, which presents either a compressed air nozzle or a rotating brush, there must be provided additionally the suction device.

It is the purpose of the present invention to avoid the disadvantages of the known devices and especially to provide a device for detaching and winding off the yarn end from a body of wound-up yarn which, in operation, is free from disturbances and is simplidied in construction.

Summary of the Invention According to the present invention, this problem is primarily resolved by providing for feeding with compressed air at least three, preferably four nozzles arranged concentrically around the bobbin and directed towards the same. By this arrangement, it is possible in a most simple manner to dispense with a driving mechanism for the bobbin since there is a current of air around the whole bobbin even when the bobbin stands still, which assures safe detaching of the yarn end as well as a rapid winding off procedure. It may be stated, however, that in certain cases, for increasing efficiency, the bobbin may be rotated, but this measure is clearly not essential.

The direction of the nozzles towards the bobbin should preferably by oblique, in order to assure on the one hand reliable detachment of the yarn end by a component of the compressed air jet and, on the other hand, to achieve rapid winding off by the compressed air moving away in the longitudinal direction of the bobbin.

A particularly reliable method of detaching the yarn may be achieved if, for continuous modification of the relative position of bobbin with respect to the nozzles as well as for causing the jet of compressed air from each nozzle to travel from one end of the bobbin in the longitudinal direction towards the other end, either the bobbin or the nozzle or both are provided with a driving device.

Winding off and removal of the detached yarn is advantageously simplified by arranging the nozzles concentrically near the opening of a reception tube, and by having the nozzle openings directed into the tube so that the yarn end detached from the bobbin is driven into the tube by the current of air.

The present invention may be realized in a particularly simple manner if the nozzles and the reception tube are connected with each other and fixed with respect to each other and if in this case the tube opening has a somewhat bigger interior diameter than the outer diameter of the bobbin so that the bobbin can be inserted into the tube opening, the nozzles for accelerating the issuing compressed air and for detaching and winding off the yarn end being directed immediately towards the space of circular cross-section remaining between the bobbin and the tube opening.

Thereby, equally reliable detaching and rapid winding off of the yarn is achieved especially if the nozzles are arranged at an angle of approximately 45 with respect to the longitudinal axis of the bobbin.

As can be seen, the inventive contents and the technical progress of the object of the present invention are assured by the new individual features as well as by their combinations and sub-combinations.

The invention will hereinafter be described in more detail by means of practical examples shown in the accompanying drawings, wherein:

FIG. 1 shows schematically a device for detaching and winding off a yarn end from a bobbin;

FIG. 2 shows a top elevation of the arrangement of a nozzle assembly shown in FIG. 1;

FIG. 3 shows a modification of the device of FIG. I with a reception tube adapted to the diameter of the bobbin, the device being shown in an idle condition; and

FIG. 4 shows the device of FIG. 3 in an operative condition.

In the example of FIG. 1, a bobbin 1 bearing a body of wound-up yarn 2 is fixed on a holder 3 which may be vertically displaced by a driving device 3a. Concentrically with the bobbin 1 on a ring 5 (FIG. 2) are arranged nozzles 4 for the acceleration of compressed air delivered thereto so that, upon starting a source of compressed air (not shown) connected to the ring 5 by an inlet duct, the yarn end 6 is detached from the body of wound-up yarn 2 by the compressed air issuing from the nozzles 4 and is whirled into a reception tube 7. Starting of the current of compressed air can be effected if the holder 3, upon actuation of the driving device 3a, is moved with respect to the support 8 and the bobbin is thus brought into the zone of influence of the jets 4. The duration of actuation of the nozzles can clearly be controlled by a control device (not shown) in the reception tube 7 which stops the feeding of compressed air as soon as the yarn end 6 has reached the reception tube 7.

It is also possible then to control alternatively the driving device 3a by means of a surveying device until, upon movement of the body of wound-up yarn 2 past the jets 4, the yarn end 6 is detached and is whirled into the reception tube 7.

FIGS. 3 and 4 show a modified example of the present invention in which the inner diameter of the reception tube 7 has been adapted to the outer diameter of the body of wound-up yarn 2. The size is then chosen so that, when the holder is in its elevated position (FIG. 4), the body of wound-up yarn 2 is completely encircled by the reception tube and the jets 4 are thus directed towards the annular gap between tube 7 and wound-up yarn body 2 that the compressed air passes at a high speed and accordingly takes with it the yarn end 6.

The angle between the nozzle 4 and the surface of the wound-up yarn body is then approximately 45 in order to obtain force components that are normal to the bobbin to detach the yarn end and also in the longitudinal direction of the bobbin for winding off the yarn end 6.

As can be seen, in mose cases, it is the simplest procedure to equip the holder 3 with the driving device 3a and to thereby insert the body of wound-up yarn into the reception tube fixed on the support 8. In certain cases however, it is also possible to arrange the holder 3 stationarily and accordingly to provide the nozzles 4 and the reception tube 7 with a driving device. As a further alternative, a driving device may be provided for the holder 3 as well as a driving device for the group of nozzles 4. In each case the jet of compressed air from each nozzle is caused to travel from one end of the bobbin in the longitudinal direction of the bobbin to the other end.

Evidently, the invention permits, generally speaking, detaching and winding off of yarn ends from a body of wound-up yarn in a most simple manner without the necessity to rotate the bobbin or to provide additional suction devices. This is particularly advantageous when the device is used for feeding yarn to an automatic yarn connecting device on a ring spinning machine.

I claim:

1. A device for detaching and winding off the exposed yarn end from a body of wound-up yarn on a bobbin by means of compressed air, comprising a holder for a bobbin; a duct system for compressed air comprising an inlet duct, at least three outlet nozzles arranged concentrically around and directed towards the axis of said bobbin when mounted on said holder, and intermediate duct means connecting said inlet duct 0t said nozzles; a driving device for effecting relative to-and-fro movement in the direction of the of said bobbin, between of said holder and said duct-system, said nozzles being directed to detach and wind off the exposed yarn end from said bobbin; and a reception tube mounted to receive said yarn end when detached from said bobbin, said reception tube having an open end directed towards said nozzles.

2. A device as defined in claim 1, in which there are precisely four outlet nozzles equidistantly arranged round said bobbin.

3. A device as defined in claim 1, in which, for continuous modification of the relative position of said bobbin holder with respect to said nozzles and for causing a jet of compressed air from each nozzle, when said duct system is supplied with compressed air, to traverse said bobbin, said driving device is arranged to cause said nozzles to travel from one end of the bobbin in the longitudinal direction to the other end thereof.

4. A device as defined in claim 1, in which said nozzles are concentrically arranged at said inlet end of said reception tube and said nozzles are so directed into said tube that the yarn end detached from the bobbin is brought into said tube by the air current emanating from said nozzles.

5. A device as defined in claim 1, comprising a stationary support, said duct system and said reception tube being fixed to said support, said tube opening having a diameter enabling the bobbin to be inserted into said tube opening with a gap providing annular clearance thereabout, and said nozzles being directed immediately towards said gap.

6. A device as defined in claim 5, in which said jets are directed obliquely towards the bobbin.

7. A device as defined in claim 5, in which said nozzles are arranged at an angle of approximately 45 with respect to the longitudinal axis of the bobbin.

l l =l =l 

1. A device for detaching and winding off the exposed yarn end from a body of wound-up yarn on a bobbin by means of compressed air, comprising a holder for a bobbin; a duct system for compressed air comprising an inlet duct, at least three outlet nozzles arranged concentrically around and directed towards the axis of said bobbin when mounted on said holder, and intermediate duct means connecting said inlet duct to said nozzles; a driving device for effecting relative to-and-fro movement, in the direction of the axis of said bobbin, between said holder and said duct system, said nozzles being directed to detach and wind off the exposed yarn end from said bobbin; and a reception tube mounted to receive said yarn end when detached from said bobbin, said reception tube having an open end directed towards said nozzles.
 2. A device as defined in claim 1, in which there are precisely four outlet nozzles equidistantly arranged round said bobbin.
 3. A device as defined in claim 1, in which, for continuous modification of the relative position of said bobbin holder with respect to said nozzles and for causing a jet of compressed air from each nozzle, when said duct system is supplied with compressed air, to traverse said bobbin, said driving device is arranged to cause said nozzles to travel from one end of the bobbin in the longitudinal direction to the other end thereof.
 4. A device as defined in claim 1, in which said nozzles are concentrically arranged at said inlet end of said reception tube and said nozzles are so directed into said tube that the yarn end detached from the bobbin is brought into said tube by the air current emanating from said nozzles.
 5. A device as defined in claim 1, comprising a stationary support, said duct system and said reception tube being fixed to said support, said tube opening having a diameter enabling the bobbin to be inserted into said tube opening with a gap providing annular clearance thereabout, and said nozzles being directed immediately towards said gap.
 6. A device as defined in claim 5, in which said jets are directed obliquely towards the bobbin.
 7. A device as defined in claim 5, in which said nozzles are arranged at an angle of approximately 45* with respect to the longitudinal axis of the bobbin. 